AB0411 ASSOCIATION BETWEEN ETHNICITY AND INITIAL RESPONSE TO TNF INHIBITORS IN PEOPLE WITH RHEUMATOID ARTHRITIS: RESULTS FROM THE BRITISH SOCIETY FOR RHEUMATOLOGY BIOLOGICS REGISTER FOR RHEUMATOID ARTHRITIS (BSRBR-RA)
Authors: M. F. Tsoi, R. S. Andev, L. Kearsley-Fleet, K. Watson, S. Dubey, K. Kumar, A. Moorthy, M. Gupta, A. Adebajo, K. Hyrich
Journal: Annals of the Rheumatic Diseases (2023)

<h3>Background</h3> Little is known about the association between ethnicity and response to TNF inhibitors (TNFi) in people with rheumatoid arthritis (RA). <h3>Objectives</h3> This study examines the association between self-reported ethnicity and DAS28 response after 6 months of treatment in patients starting their first TNFi using data from the British Society for Rheumatology Biologics Register for RA. <h3>Methods</h3> 14133 RA patients with self-reported ethnicity starting their first TNFi were included. Due to a very low proportion of non-white patients, ethnicity was divided into white or non-white for analysis. Outcomes included the change in disease activity using DAS28, the proportion of patients who achieved DAS28 remission and EULAR response at month 6. Adjusted regression models appropriate to outcome were used to compare between the two groups. Multiple imputation was used to account for missing data. <h3>Results</h3> Of 14133 patients starting TNFi with recorded ethnicity, only 607 (4.3%) recorded themselves as non-white (389 Asian, 134 Black, 57 Mixed ethnicity and 27 other) (Table 1). At start of TNFi, non-white patients were younger (non-white vs. white: mean 51 vs. 57 years; p&lt;0.001), with shorter disease duration (median 8 vs. 10 years; p&lt;0.001), higher proportion of females (86% vs. 76%; p&lt;0.001) and fewer current cigarette smokers (9% vs. 20%; p&lt;0.001). Non-white patients had lesser improvement in DAS28 at month 6 (adjusted regression coefficient (95% confidence interval (95%CI)): 0.3 (0.04-0.5)). However, using the white patients as a reference, non-white patients were not associated with the achievement of DAS28 remission (adjusted odds ratio (95%CI): 0.7 (0.5-1.1)) or EULAR response (aOR (95%CI): 0.8 (0.7-1.0)) at month 6. <h3>Conclusion</h3> Recruitment to the BSRBR-RA of non-white patients was exceptionally low compared to expected population distribution – the reasons for this are not immediately evident. Among those recruited, there were no significant differences observed in initial treatment response although non-white patients were younger, more likely to be female, had shorter disease duration and less likely to be smokers. Further evaluation into both ways to increase representativeness in our national RA treatment register and influence of ethnic differences on longer term outcomes with biologic therapies is warranted. <h3>Reference</h3> NIL. <h3>Acknowledgements:</h3> NIL. <h3>Disclosure of Interests</h3> Man Fung Tsoi: None declared, Rajinder Singh Andev Speakers bureau: Speaker fees from Novartis, Lianne Kearsley-Fleet: None declared, Kath Watson: None declared, Shirish Dubey Speakers bureau: Speaker fees from Janssen, Consultant of: Honoraria from Boehringer Ingelheim, Kanta Kumar: None declared, Arumugam Moorthy Speakers bureau: Novartis and Galapagos, Consultant of: Honoraria from Lilly and UCB, Monica Gupta: None declared, Adewale Adebajo: None declared, Kimme Hyrich Consultant of: Honoraria from Abbvie, Grant/research support from: Pfizer and BMS, and is supported by the NIHR Manchester Biomedical Research Centre.